Kommands

Overview

Kommands is a command writing mod that can be used to create commands with syntax completion in game! This mod is completely client sided, but can be used to create aliases for server commands. See the example configuration for how the syntax works. There is also a wiki.
 
When first loaded up some prebuilt commands will be in the directory <minecraftDir>/config/kommands/commands/sample_config.toml. There is a brief tutorial on how to create commands in there.

Examples

Prebuilt commands are:

Calculate – /calc – Calculates an expression
Up – /up [] [] – /setblocks the black you’re standing in and teleports you above it
Relative Fill – /relfill – Fills a cube of block type amount of blocks around you